BFS求解迷宫最短路径

<p>本文使用BFS广度优先搜索算法实现求解迷宫的最短路径（C++），使用到了队列先进先出的性质，依次搜索路径直到找到目标出口（如果迷宫能走通）求解到的路径即为该迷宫的最短路径，找到返回true，找不到返回false，本文使用vexmap一个map容器记录队列的搜索路径（记录队列路径的实现有点草率，可以再优化）。</p><p> </p><pre class="cpp" name="code">#include<iostream>#include<queue>using namespace std;typedef unsigned long long iUINT64;map<iUINT64,int> vexmap;const int g_errNUM = 88888;offsets myMove4[4] = {//各个方向的偏移表{-1,0,"N"},{0,1,"E"},{1,0,"S"},{0,-1,"W"},};class  Itmes{public:iUINT64 x,y;//偏移量x,y和试探方向Itmes():x(g_errNUM),y(g_errNUM){}};bool BFS(Itmes star,Itmes end,int& cntNum){cntNum = 0;iUINT64 curx,cury,searchx,searchy;queue<Itmes> ItemQ;ItemQ.push(star);iUINT64 Star = star.x << 32 | star.y;vexMap[Star] = g_errNUM;mark[star.x][star.y] = 1;while (!ItemQ.empty()){Itmes tmp = ItemQ.front();curx = tmp.x; cury = tmp.y;ItemQ.pop();for (int i = 0; i < 4; i++){searchx = curx + myMove4[i].a;searchy = cury + myMove4[i].b;if (Maze[searchx][searchy] == 0 && mark[searchx][searchy] == 0){mark[searchx][searchy] = 1;Itmes tmp2;tmp2.x = searchx;tmp2.y = searchy;iUINT64 NodeCur = curx << 32 | cury;iUINT64 NodeSearch = searchx << 32 | searchy;vexMap[NodeSearch] = NodeCur;ItemQ.push(tmp2);//出口条件if (searchx == end.x && searchy == end.y){iUINT64 Index = searchx << 32 | searchy;while (vexMap[Index] != g_errNUM){Index = vexMap[Index];cntNum++;if (cntNum > 1000000)//防护防止出现死循环，可优化{return false;}}return true;}}}}return false;}